Automatic pressure and vacuum clearing skid method

ABSTRACT

A method of pressurization and evacuation of a system including during a pressurization phase; introducing a pressurized gas stream into the top valve, which is actuated to direct the pressurized gas stream into the bottom valve, wherein the bottom valve is actuated to direct the pressurized gas stream to the customer apparatus; and during a vacuum phase; introducing the pressurized gas stream into the top valve, which is actuated to direct the pressurized gas stream into the inlet port of the pressure inlet of the educator, thereby producing a low pressure condition in the suction inlet, introducing a customer gas stream into the bottom valve, which is actuated to direct the customer gas to exit the bottom valve, wherein the low pressure condition causes the customer gas stream to be directed to the educator suction inlet, wherein it mixes with the pressurized gas stream and exits the educator discharge outlet.

BACKGROUND

In industrial chemical and petrochemical processes, gaseous nitrogen isused for a number of purposes. Nitrogen is largely inert, and as such iscommonly used to displace undesired gases in various processes. Onecommon example is the use of gaseous nitrogen to displace air as aninert blanket. Nitrogen does engage in certain chemical reactions and,for example, is useful in the production of ammonia. Gaseous nitrogen isoften provided to the end user as a commodity, for example by means ofan “over the fence” supply from an existing nitrogen pipeline or from atanker truck. Many processes that use nitrogen are have pressurelimitations, either high, low, or both, that must be maintained.

SUMMARY

In another embodiment of the present invention, a method ofpressurization and evacuation of a system including during apressurization phase; introducing a pressurized gas stream into the topvalve, which is actuated to direct the pressurized gas stream into thebottom valve, wherein the bottom valve is actuated to direct thepressurized gas stream to the customer apparatus; and during a vacuumphase; introducing the pressurized gas stream into the top valve, whichis actuated to direct the pressurized gas stream into the inlet port ofthe pressure inlet of the educator, thereby producing a low pressurecondition in the suction inlet, introducing a customer gas stream intothe bottom valve, which is actuated to direct the customer gas to exitthe bottom valve, wherein the low pressure condition causes the customergas stream to be directed to the educator suction inlet, wherein itmixes with the pressurized gas stream and exits the educator dischargeoutlet.

BRIEF DESCRIPTION OF THE FIGURES

For a further understanding of the nature and objects for the presentinvention, reference should be made to the following detaileddescription, taken in conjunction with the accompanying drawings, inwhich like elements are given the same or analogous reference numbersand wherein:

FIG. 1 illustrates a schematic representation of the system indicatingthe ports, inlets, and outlet on the 3-way valves and the eductor, inaccordance with one embodiment of the present invention.

FIG. 2 illustrates a schematic representation of the pressurizationphase, in accordance with one embodiment of the present invention.

FIG. 3 illustrates a schematic representation of the vacuum phase, inaccordance with one embodiment of the present invention.

FIG. 4 illustrates a representation of the top 3-way valve and thebottom 3-way valve with individual actuators, in accordance with oneembodiment of the present invention.

FIG. 5 illustrates a representation of the top 3-way valve and thebottom 3-way valve with a single actuator, in accordance with oneembodiment of the present invention.

FIG. 6 illustrates a representation of the valves indicating the portorientations in the pressurization phase, in accordance with oneembodiment of the present invention.

FIG. 7 illustrates a representation of the valves indicating the portorientations in the vacuum phase, in accordance with one embodiment ofthe present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

Illustrative embodiments of the invention are described below. While theinvention is susceptible to various modifications and alternative forms,specific embodiments thereof have been shown by way of example in thedrawings and are herein described in detail. It should be understood,however, that the description herein of specific embodiments is notintended to limit the invention to the particular forms disclosed, buton the contrary, the intention is to cover all modifications,equivalents, and alternatives falling within the spirit and scope of theinvention as defined by the appended claims.

It will of course be appreciated that in the development of any suchactual embodiment, numerous implementation-specific decisions must bemade to achieve the developer's specific goals, such as compliance withsystem-related and business-related constraints, which will vary fromone implementation to another. Moreover, it will be appreciated thatsuch a development effort might be complex and time-consuming, but wouldnevertheless be a routine undertaking for those of ordinary skill in theart having the benefit of this disclosure.

ELEMENT LEGEND

-   -   101=Gas Source (Nitrogen, etc) entering First Port of Top 3-Way        Valve    -   102=Top 3-Way Valve    -   103=First conduit    -   104=Second conduit    -   105=First Check Valve    -   107=Bottom 3-Way Valve    -   108=Fourth conduit    -   109 a=Stream to Customer Equipment (apparatus)    -   109 b=Stream from Customer Equipment    -   110=First Pressure Safety Valve    -   111=Second Check Valve    -   113=Second Pressure Safety Valve    -   114=Eductor    -   115=Third conduit    -   116=Stream to Flare    -   117=Pressure Indicator    -   118=Top 3-way valve first port    -   119=Top 3-way valve second port    -   120=Top 3-way valve third port    -   121=Bottom 3-way valve first port    -   122=Bottom 3-way valve second port    -   123=Bottom 3-way valve third port    -   124=Eductor pressure inlet    -   125=Eductor suction inlet    -   126=Eductor discharge outlet    -   127=First actuator (Top 3-way valve)    -   128=Second actuator (Bottom 3-way valve)    -   129=Common actuator (Top 3-way valve and Bottom 3-way valve)

Turning to FIG. 1, a pressurization and evacuation system is presented.The system includes a top 3-way valve 102 that includes a first port118, a second port 119, and a third port 120. The system includes abottom 3-way valve 107 that includes a first port 121, a second port122, and a third port 123. The system also includes an educator 114comprising a pressure inlet 124, a suction inlet 125, and a dischargeoutlet 126.

The top 3-way valve third port 120 is fluidically connected with theeducator pressure inlet 124 by with a first conduit 103. The firstconduit 103 may also include a second check valve 111 in fluidicconnection with the top 3-way valve third port 120 and the educatorpressure inlet 124. The first conduit may include a second pressuresafety valve 113 in fluidic connection with the first conduit.

The top 3-way valve second port 119 is fluidically connected with thebottom 3-way valve first port 121 by a second conduit 104. The secondconduit 104 may also include a first check valve 105 in fluidicconnection with the top 3-way valve second port 119 and the bottom 3-wayvalve first port 121.

The bottom 3-way valve third port 123 is fluidically connected with theeducator suction inlet 125 with a third conduit 115. The bottom 3-wayvalve second port 122 is connected with a customer apparatus (not shown)with a fourth conduit 108. The fourth conduit 108 may include a firstpressure safety valve 110.

As indicated in FIG. 4, the top 3-way valve 102 may be controlled by afirst actuator 127, and the bottom 3-way valve 107 may be controlled bya second actuator 128. As indicated in FIG. 5, the top 3-way valve 102and the bottom 3-way valve 107 may be controlled by a common actuator129. The first actuator 127 and/or the second actuator 128 and/or thecommon actuator may be of a type selected from the group consisting ofan electric actuator, a pneumatic actuator, and a hydraulic actuator. Inthe interest of simplicity, FIGS. 6 and 7 indicate a common actuator,but one of ordinary skill in the art will readily understand how such anarrangement may also be operated with 3-way valves operated by separateactuators.

The system may include a pressure indicator 117 that is in fluidicconnection with the fourth conduit 108. The pressure indicator 117 mayprovide a signal to the top 3-way valve 102, and/or the pressureindicator may provide a signal to the bottom 3-way valve 107.

Turning to FIG. 2, a pressurization method is presented, utilizing thesystem as described above. During the pressurization phase a pressurizedgas stream 101 is introduced into the first port 118 of the top 3-wayvalve 102. The top 3-way valve 102 is then actuated to direct thepressurized gas stream 101 to exit the second port 119 of the top 3-wayvalve 102 and enter second conduit 104. Downstream of the second port119 of the top 3-way valve may be a first check valve 105 in order toprevent back flow.

The pressurized gas stream from second conduit 104 is introduced intothe first port 121 of the bottom 3-way valve 107, the bottom 3-way valve107 is then actuated to direct the pressurized gas stream to exit thesecond port 122 of the bottom 3-way valve 107 and to enter fourthconduit 108. Downstream of the second port 122 of the bottom 3-way valve107 may be a pressure indicator 117 and/or a first pressure safety valve110. The pressurized gas then exits fourth conduit 108 and enters thecustomer apparatus (not shown).

Turning to FIG. 3, a vacuum method is presented, utilizing the system asdescribed above. During the vacuum phase the pressurized gas stream 101is introduced into the first port 118 of the top 3-way valve 102. Thetop 3-way valve 102 is then actuated to direct the pressurized gasstream to exit the third port 120 of the top 3-way valve 102 and enterfirst conduit 103. Downstream of the third port 120 of the top 3-wayvalve may be a second check valve 111 in order to prevent back flow,and/or a second pressure safety valve 113.

The pressurized gas stream from the first conduit 103 is introduced intothe educator pressure inlet 124, thus producing a low pressure conditionin the suction inlet. A customer gas steam 109 a is then introduced intothe second port 122 of the bottom 3-way valve 107. The bottom 3-wayvalve 107 is then actuated to direct the customer gas to exit the thirdport 123 of the bottom 3-way valve 107. The low pressure condition thencauses the customer gas stream to be directed to the educator suctioninlet 125, wherein it mixes with the pressurized gas stream 124 andexits the educator discharge outlet 126 and to a conduit to exhaust orflare 116. The pressurized gas stream may be an inert gas. Thepressurized gas stream may be nitrogen.

Turning to FIG. 4, the top 3-way valve 102 may be controlled by a firstactuator 127, and the bottom 3-way valve 107 may be controlled by asecond actuator 128. Either the first actuator 127 or the secondactuator 128, or both actuators, may be an electric actuator, apneumatic actuator, or a hydraulic actuator.

Turning to FIG. 5, the top 3-way valve 102 and the bottom 3-way valve107 may be controlled by a common actuator 129. Either the commonactuator 129 may be an electric actuator, a pneumatic actuator, or ahydraulic actuator.

One embodiment of the respective valve port orientation and status for asingle actuator arrangement for the pressurization phase is illustratedin FIG. 6. One embodiment of the respective valve port orientation andstatus for a single actuator arrangement for the vacuum phase isillustrated in FIG. 7. One of ordinary skill in the art will readilyunderstand how such an arrangement may also be operated with 3-wayvalves operated by separate actuators.

Turning to FIGS. 2 and 3, a pressure indicator 117 may be in fluidicconnection with the fourth conduit 108, and the pressure indicator 117may provide a signal to the first actuator 127 and/or the secondactuator 128. The vacuum phase may be initiated when the pressureindicator 117 senses a pressure above a first predetermined threshold.The pressurization phase may be initiated when the pressure indicator117 senses a pressure below a second predetermined threshold. The systembegins normal operation with the pressure indicator 117 at ambientpressure.

It will be understood that many additional changes in the details,materials, steps and arrangement of parts, which have been hereindescribed in order to explain the nature of the invention, may be madeby those skilled in the art within the principle and scope of theinvention as expressed in the appended claims. Thus, the presentinvention is not intended to be limited to the specific embodiments inthe examples given above.

What is claimed is:
 1. A method of pressurization and evacuation of asystem comprising: a pressurization and evacuation system comprising: atop 3-way valve comprising an first port, a second port and a port, abottom 3-way valve comprising an first port, a second outlet port and athird port, and an educator comprising a pressure inlet, a suctioninlet, and a discharge outlet, wherein: a first conduit fluidicallyconnects the top 3-way valve third port with the educator pressureinlet, a second conduit fluidically connects the top 3-way valve secondport with the bottom 3-way valve first port, a third conduit fluidicallyconnects the bottom 3-way valve third port with the educator suctioninlet, and a fourth conduit fluidically connects the bottom 3-way valvesecond port with a customer apparatus; the method comprising, during apressurization phase: introducing a pressurized gas stream into thefirst port of the top 3-way valve, wherein the top 3-way valve isactuated to direct the pressurized gas stream to exit the second port ofthe top 3-way valve, introducing the pressurized gas stream into thefirst port of the bottom 3-way valve, wherein the bottom 3-way valve isactuated to direct the pressurized gas stream to exit the second port ofthe bottom 3-way valve and to the customer apparatus; the methodcomprising, during a vacuum phase: introducing the pressurized gasstream into the first port of the top 3-way valve, wherein top 3-wayvalve is actuated to direct the pressurized gas stream to exit the thirdport of the top 3-way valve, introducing the pressurized gas stream intothe inlet port of the pressure inlet of the educator, thereby producinga low pressure condition in the suction inlet, introducing a customergas stream into the second port of the bottom 3-way valve, wherein thebottom 3-way valve is actuated to direct the customer gas to exit thethird port of the bottom 3-way valve, wherein the low pressure conditioncauses the customer gas stream to be directed to the educator suctioninlet, wherein it mixes with the pressurized gas stream and exits theeducator discharge outlet.
 2. The method of pressurization andevacuation of a system of claim 1, wherein the pressurized gas streamcomprises an inert gas.
 3. The method of pressurization and evacuationof a system of claim 2, wherein the inert gas is nitrogen.
 4. The methodof pressurization and evacuation of a system of claim 1, wherein the top3-way valve is controlled by a first actuator and the bottom 3-way valveis controlled by a second actuator.
 5. The method of pressurization andevacuation of a system of claim 4, wherein the first actuator is of atype selected from the group consisting of an electric actuator, apneumatic actuator, and a hydraulic actuator.
 6. The method ofpressurization and evacuation of a system 4, wherein the second actuatoris of a type selected from the group consisting of an electric actuator,a pneumatic actuator, and a hydraulic actuator.
 7. The method ofpressurization and evacuation of a system of claim 1, wherein the top3-way valve and the bottom 3-way valve are controlled by a singleactuator.
 8. The method of pressurization and evacuation of a system ofclaim 7, wherein the single actuator is of a type selected from thegroup consisting of an electric actuator, a pneumatic actuator, and ahydraulic actuator.
 9. The method of pressurization and evacuation of asystem of claim 4, further comprising a pressure indicator in fluidicconnection with the fourth conduit, wherein the pressure indicatorprovides a signal to the first motor, and wherein the pressure indicatorprovides a signal to the second motor.
 10. The method of pressurizationand evacuation of a system of claim 9, wherein the vacuum phase isinitiated when the pressure indicator senses a pressure above a firstpredetermined threshold.
 11. The method of pressurization and evacuationof a system of claim 10, wherein the pressurization phase is initiatedwhen the pressure indicator senses a pressure below a secondpredetermined threshold.